Why is My Lawn Brown?

This is not an easy question to answer without first asking a few background questions. If the spots are irregular in shape, and not round, I would start with the sprinkler system.  Do you have automatic sprinklers, manually operated sprinklers, or none of the above?  How often do you water? When do you water?  How long do you water?  Next I would look at the sprinklers while they are running.  Are they operating properly?  Is the spacing allowing head to head coverage?  Are there any shrubs or trees blocking the pattern?  Are the heads level and adjusted to the right height? 

Dry spot from lack of water

A soil probe can take a core sample of the top 4-6 inches and tell you if the soil has adequate water and how deep down the water has traveled.  Ideally, you would see good moisture down 4-6 inches deep.  If you can’t get the probe down below 2-4 inches, the soil is likely water deficient.  A standard 6-8 inch screwdriver can also be an easy tool to probe how far down the soil is moist.  Generally, you should be able to push the screwdriver down 4-6 inches with moderate effort.  Too easy…too wet; too hard…too dry.

Pythium Disease

Brown lawns could also be the result of numerous pests.  Diseases generally cause circular yellow-brown patterns in the lawn and symptoms vary with the pathogen involved.  Insect damage can be somewhat random in appearance.  Some pest attack the roots causing failure of the lawn in patches while others feed on the leaves causing thinning or yellowing.

Lastly, and you may not want to hear this, but there could be several cultural habits that cause a lawn to fail during stress periods.  Over watering or watering frequently, especially in the evenings, could encourage disease activity.  Over fertilizing, especially spilling fertilizer, can cause rapid browning due to the high salt content (like pet urine burns).  Mowing too short, too infrequently, or with dull mower blades can stress the lawn as well.  Ideally they should be mowed at least weekly and at the proper height for that particular grass type.  There are also the odd things like sunlight reflection off a large picture window, placing car floor mats on the lawn while cleaning the car, construction cleanups, and space aliens landing at night. 

Hopefully, you now have some ideas on how to troubleshoot your brown spots, or you can always give us a call for a free analysis.  The weather is going to become cooler shortly and many of this summer’s brown spots will be disappearing for several months. Hooray!